Which of the following is NOT a primary vector in Ohio?

The correct answer highlights that spiders are not considered a primary vector in Ohio. In the context of vector control, primary vectors are organisms that are significant in the transmission of diseases affecting humans, wildlife, or livestock.

Mosquitoes, fleas, and ticks are all known for their roles as vectors for various pathogens. Mosquitoes, for instance, are well-known for transmitting diseases such as West Nile Virus and Zika Virus. Ticks are important vectors for Lyme disease and other tick-borne illnesses. Fleas can transmit diseases like the bubonic plague or can act as a vector for other parasites and infections.

Spiders, on the other hand, do not typically carry or transmit infectious diseases to humans in the same way that the other listed organisms do. While they can possess venom that may affect humans, they are not associated with vector-borne diseases. This distinction is crucial in vector control strategies and public health considerations in Ohio, thereby solidifying why spiders do not fall under the category of primary vectors.